A charged particle beam apparatus typified by a scanning electron microscope (SEM) is used for inspection, analysis and observation of a semiconductor wafer and so on. In this kind of apparatus, a sample moving device (sample stage) with high accuracy and high rigidity is necessary from viewpoints of securing inspection accuracy, keeping/improving throughput and so on.
The sample moving device (sample stage) is configured by combining a planar movement (XY movement) device, a rotational movement (θ movement) device, a lifting and lowering (Z movement) device and the like in accordance with a purpose of the apparatus. In particular, the lifting and lowering (Z movement) device is required to keep posture accuracy and rigidity before and after the lifting/lowering in good condition without reducing operation performance of the planar movement (XY movement) device having high movement accuracy.
There is a device described in Patent Literature 1 as the lifting and lowering (Z movement) device. In Patent Literature 1, a Z stage (6) on which RXYT stages (2 to 5) are placed is described. The Z stage (6) includes two wedge-shaped slide members (13) formed into the same shape and arranged so that inclined surfaces face each other, a feed bolt (20) in which ball screw portions (24, 25) (configured by nut portions (21, 22) provided with spirals in opposite directions to each other and bolt portions (18, 19)) connected to the two wedge-type slide members (13) through a connecting member (31) are arranged in both ends and a stepping motor (23) driving the feed bolt (20) to rotate (FIG. 1 to FIG. 3). The Z stage (6) drives the RXYT stages (2 to 5) supported by the inclined surfaces of the two wedge-type slide members (13) vertically (Z direction) by moving the ball screw portions (24, 25) in opposite directions to each other by rotation of the feed bolt (20) ([0041] to [0045]).